Provide fn_trait's
call,
call_mut, and
call_once
on Stable Rust for functions / closures with ≤ 12 arguments.fn_trait's
call,
call_mut, and
call_once
on Stable Rust for functions / closures with ≤ 12 arguments.
```rust let closure = |x: i32, y: i32, z: String| { println!("{}", z); x + y };
// Once the fn_trait feature has stabilized, you would do this.
let result = closure.call((5, 42, "Hello World"));
// For now, use PFn. let result = closure.pfn_call((5, 42, "Hello World")); ```
rust
// Here, Func can be a function or closure that takes any number of arguments (actually 1 - 12 arguments).
struct Runnable<Args, Func: PFnOnce<Args>> {
func: Func,
args: Args
}
impl<Args, Func: PFnOnce<Args>> Runnable<Args, Func> {
fn run(self) -> Func::PFnOutput {
(self.func).pfn_call_once(self.args)
}
}
let runnable = Runnable {
func: |mut x: String| {
x.push_str("!!!");
x
},
args: ("hello world".into(),)
};
assert_eq!(runnable.run(), "hello world!!!");